Cut the bread in half lengthwise. The top half will have a slightly rounded top. Cut a lengthwise strip from the crust of the top half so the bread lies flat (save the bread strip for bread crumbs, if desired). Place the bread, cut sides up on prepared sheet.

Brush bread with garlic-oil mixture. Use extra oil if necessary. Sprinkle bread with cheese then top with onions. Season with pepper. Arrange olives over then sprinkle with rosemary.